Array and collection validation

Fynix supports both plain arrays and collections of typed DTOs. Validate the collection shape first, then add item rules or object rules when needed.

Validate an array’s size

use Fynix\Rule;

$tags = Rule::array('tags')
    ->min(1)
    ->max(10)
    ->validate(['php', 'validation']);

For arrays, min() and max() count items. The limits are inclusive.

Validate every scalar item

$tags = Rule::arrayOf('tags')
    ->min(1)
    ->max(10)
    ->each(Rule::string('tag')->length(2, 30));

$errors = $tags->validateAll(['php', '']);

Use arrayOf() with each() when every item shares the same scalar rule.

Numeric collections

$quantities = Rule::arrayOf('quantities')
    ->each(Rule::integer('quantity')->min(1)->max(999));

$errors = $quantities->validateAll([2, 0, 4]);

The item rule runs for every value in the collection.

Optional collections

$attachments = Rule::arrayOf('attachments')
    ->optional()
    ->max(5)
    ->each(Rule::string('attachment')->max(255));

$errors = $attachments->validateAll(null); // []

Use optional() when the entire collection may be absent. Item rules apply only when a collection is present.

Arrays of DTOs

final class LineItem
{
    public string $sku = '';
    public int $quantity = 0;
}

$items = Rule::objectArray('items', LineItem::class)
    ->min(1)
    ->max(100);

Register LineItem rules so the handler can validate each object:

ValidationRegistry::register(
    LineItem::class,
    static fn (RuleSet $rules): array => [
        $rules->string('sku')->length(3, 30),
        $rules->integer('quantity')->min(1)->max(999),
    ],
);

$errors = ValidationHandler::validate($order);

The handler preserves item indexes in the nested error output.

Choosing the collection rule

• Use array() when only the collection itself needs validation.
• Use arrayOf() with each() for repeated scalar values.
• Use objectArray() for repeated typed DTOs.
• Use ValidationHandler when collection items have registered nested rules.